Author: Rich Walker

Introduction

So far in this series we have prepared and run a number of simulations and considered the results in Mermaid, all with the aim of answering the question:

“When should we take the trenching vessel on hire, relative to the installation vessel?”

We saw in the last post that our base case offset (32 days) is a fairly good position, however, we think there might be opportunity to improve on this. The issue we have is that our post-processing requirement is outside the type of charts and tables offered by Mermaid. Read more >

Introduction

Last time we finished the setup of the analysis by preparing the flow diagram. We considered a number of options for modelling these tasks, ultimately selecting a clean, simple and easy to maintain approach. We also performed a number of simulations.

In this post we will take a look at the results we have generated and will consider the impact these can have on our decision making. Finally, we’ll make some decisions regarding the next steps we should take.

Box Whisker Charts

In this post we are going to analyse our results using Mermaid’s “Duration Box Whisker Charts”, here’s a quick overview of the data represented by different elements of these. Read more >

Introduction

Last time we outlined the analysis of cable installation operations for a hypothetical operation at WaveHub. We looked at the map and the shelter characteristics of the vessels we intend to use and outlined the main objective of the analysis, which is:

“When should we take the trenching vessel on hire, relative to the installation vessel?”

In addition we sketched out our operations, at quite a high level, ahead of putting them in to Mermaid, this sketch is shown below:

In this post we are going to look at how we can model these operations in Mermaid and consider, in a little more detail, how we vary the length of the lay and trench operations. Read more >

Mojo Maritime will be attending All Energy 2016 and showcasing Mermaid®, the market-leading marine operations planning and risk optimisation tool.

In a speaking slot during the “UK Marine enabling technology programmes” session (in the Lomond Auditorium at 4pm on 4th May), Steve Jermy will present a number of innovative solutions developed by Mojo Maritime, including the HF4 vessel. Mermaid underpinned the development of these solutions and Steve will discuss how and why Mermaid can benefit other projects. Read more >

Introduction

Marine operations often require multiple vessels which are assigned specific tasks to perform. Often the tasks performed by the vessels are independent of each other (i.e. the vessels work alone) but are linked in such a way that one vessel is dependent on the other completing work. In this series of posts we are going to consider cable lay and trenching operations using two assets. We’ll also look at the consideration of the simulation results both in Mermaid and as part of a bespoke analysis outside Mermaid. Read more >

Our latest release is now out and adds some new features to improve the usability of Mermaid and to allow further interrogation of your results sets.

New Features

MM-1289: Display comparative results in Exceedance charts.

It is now possible to plot data from multiple simulations on one Exceedance chart, allowing direct visual comparison of the results. To plot multiple results sources on one chart use the control keyboard key to multi-select in the “Results Source” box under “Chart Options”. It is also now possible to name results sources rather than using their file names. Read more >

In this post we’re going to look at bringing the foundations to the installation vessel at site. It’s thought that, as with carrying more components, we can increase the working time by transiting less. If another vessel (a barge and tugs) brings components to the main vessel the transit requirements are reduced, although it’s worth noting that offshore transfers of this type are quite strictly limited; the trade-off between transit reduction and sensitive operations is the main concern here.

The Simulation

Our base case simulation includes the transfer of installation components to the installation vessel from a storage barge in the port. Read more >

Indefinite suspensions

For a long time it has been possible to allow tasks and groups of work in Mermaid to suspend, meaning that work is allowed to stop once it has started but before it is complete. There are two cases for this, Fully Suspendable which allows the vessel to come and go as it pleases, and If Holding Station which requires the vessel(s) to remain at the working location throughout the suspension. In both cases the length of time for which work can stop has been unlimited. Read more >